Conventional Cigarette
Note: This virtual cigarette does not represent a particular brand but
describes the structure of many of the most popular brands of cigarettes on the
market.

Tobacco
Only a portion of the tobacco inside a cigarette comes from the leaf of a
tobacco plant. A significant amount of the shredded brown innards of most
modern cigarettes is a paper product called "reconstituted tobacco" or
"homogenized sheet tobacco," which is made from a pulp of mashed tobacco stems
and other parts of the tobacco leaf that would otherwise go to waste.
Manufacturers spray and impregnate reconstituted tobacco paper with nicotine
and other substances lost during the process, along with as many as 600
chemical additives. These include several that may come as a surprise, such as
ammonia, which aids in the delivery of nicotine, and chocolate, which masks the
bitter taste of tobacco. Finally, the 'recon' is sliced to resemble shredded
leaf tobacco.

In addition to reconstituted tobacco, cigarette companies pack cigarettes with
so-called puffed tobacco (also called "expanded tobacco"), which allows them to
produce more cigarettes per pound of tobacco grown with lower levels of tar
particles in the smoke. Manufacturers saturate this tobacco, which they make
from the leaf of the plant, with freon and ammonia gases and then freeze-dry
it. This process expands the tobacco, increasing its volume to at least double
its natural state.

Paper wrap
Though seemingly innocuous, cigarette paper is largely responsible for the rate
at which a cigarette burns and the amount and density of the smoke it produces.
The paper displays a pattern of concentric circle striations called "burn
rings." The burn rings correspond to two different thicknesses in the paper,
which serve to precisely control the speed at which the cigarette burns,
slowing it automatically when the smoker is not inhaling in order to prolong
the cigarette's consumption and speeding it up as the smoker takes a drag so as
to maximize smoke intake. In addition, like the tobacco, the cigarette paper
contains a host of chemicals, among them titanium oxide, which accelerates and
maintains burning so the cigarette does not go out and the smoke is delivered
evenly with each puff. These chemicals have contributed to many
cigarette-caused fires, a problem that some manufacturers have not addressed
until recently.

Filter
The filter cigarette was a specialty item until 1954, when manufacturers
introduced it broadly following a spate of speculative announcements from
doctors and researchers concerning a possible link between lung diseases and
smoking. Reacting to smokers' voiced fears and sudden reduced cigarette
consumption, cigarette companies, by altering the filter's structure and
materials, began making competing claims about how low their brands' tar and
nicotine levels were.

Some cigarettes today boast the inclusion of a "charcoal filter" in addition to
the more common dense, synthetic fiber filters seen in almost all filter
cigarettes. Manufacturers claim that charcoal filters, which contain bits of
charcoal embedded within the fiber filters, reduce certain toxins in the smoke.
But no evidence exists that these cigarettes are significantly less dangerous
for the user.

Most filter cigarettes also bear ventilation holes punched around the
circumference of the filter tip. (Regular cigarettes might feature one ring of
ventilation holes, while light and ultra-light cigarettes of the same brand
might have two or more rings.) These tiny holes, which you can see by holding
the unrolled paper up to a bright light, can allow enough fresh air into the
smoke that such cigarettes can test quite low in tar and nicotine levels when
smoked by machines, which do not cover the holes. However, smokers' fingers or
lips often cover some of these holes as they puff, giving them much higher
doses of tar and nicotine than advertised. According to critics of the tobacco
industry, the holes create a flexible dosing system that allows addicted
smokers to maintain the tar and nicotine levels they crave while believing they
are receiving lower, safer doses.

'Safer' Cigarettes
Note: In the past 25 years, major U.S. cigarette manufacturers have tried to
develop reduced-hazard cigarettes. The brands below are just two of the many
'safer' cigarette prototypes.

Eclipse

In 1994, R.J. Reynolds began testing its Eclipse smokeless cigarette with
consumers in select U.S. markets. Most scientists and health professionals
agree that the combustion of tobacco creates most of the toxins in a typical
cigarette. The presumed relative safety of Eclipse, which from a distance looks
like a conventional cigarette, rests on the fact that only a small amount of
the tobacco inside it actually burns. Instead, when a smoker lights a charcoal
tip on the end of the cigarette, a column of processed tobacco laced with
glycerin and flavors heats up. The warmed glycerin produces a smoke-like vapor,
which carries nicotine released by the heat into the lungs. Because of the
burning charcoal tip, carbon monoxide remains a constituent of the smoke, and
overall toxin levels increase when the tip burns hot from heavy smoking.

It remains to be seen how well Eclipse will sell in the U.S. and, with further
testing, whether or not it will live up to the claim that it may be a safer
smoke. One benefit of Eclipse is that it significantly reduces harmful
secondhand smoke.

Accord

In certain markets in the U.S. and Japan, Philip Morris is testing its version
of a 'safer' cigarette, Accord. On the market since 1998, Accord includes two
elements, a cigarette-like roll of tobacco (which cannot be conventionally
burned) and a battery-powered heating device. The smoker inserts the special
cigarette into a hole in the pager-sized heater and smokes the cigarette in
conjunction with the heater. A microchip inside the heater controls each puff
of the cigarette, delivering a specific amount of heated tobacco vapor to the
smoker each time he or she takes a drag.

Very little of the tobacco inside the Accord cigarette actually burns, so
neither ashes nor appreciable amounts of secondhand smoke result. At the top of
the device, an LCD screen turns on when the smoker inserts an Accord cigarette,
and as the smoker takes a drag, it reads out how many of a total of seven puffs
remain in the cigarette. This high-tech smoking system costs an initial $40,
which buys the consumer a carton of special Accord cigarettes, the electronic
device, and a battery charger for renewing the heater after each pack of the
special cigarettes.